As is known, devices are currently commercially available which adjust the flow-rate of a fluid, particularly medical oxygen, by using a disk with calibrated holes which are connected to the user device in each instance.
Such devices are generally arranged downstream of a pressure reduction unit, which must be provided with a means for throttling the high-pressure flow of fluid.
Several drawbacks are currently encountered with the solutions of the background art: one is the fact that it is necessary to provide two separate elements, i.e., the pressure reduction unit, with its corresponding flow control element, and the flow-rate adjustment device with its actuation handwheel, thus causing problems in use and problems in terms of space occupation due to the presence of two separate elements.
Another problem further consists in that the disks with calibrated holes, which typically rotate with respect to the port that controls the flow of the low-pressure fluid, can be subject to deformations, since in order to try to optimize the precision of the holes it is necessary to use relatively low thicknesses.
Another problem further consists in that in the solutions of the background art, when changing the flow-rate, the output port for the passage of the fluid may accidentally arrange itself in a region which does not allow the passage of the fluid, with consequent severe risks for the patient.